Projection screen



" fggfw I SEARCH ROOM OGL 4, 1932' y A c. PAYNE ET A1.

l 4 nossc'rrou scasn .FBSTITUTE FR'MISS'NG OR 19g-igual .Filed Nav. 2a,192s A o i 5%, Www-:mung

Patented Oct. 4, 1932 PATENT OFFlCE ARTHUR C. PAYNE, F KEW GARDENS, ANDDAVID F. NEWMAN, OF FREI-EPORT, NEW

YORK, ASSIGNORS TO TRANS-LUX DAYLIGHT PICTURE SCREEN CORYORATION, OF'

NEW YORK, N. Y., A CORPORATION OF DELAWARE rnoJEcrIoN SCREEN.Application led November 28, 1925, Serial No. 72,029. Renewed May 24,1930.

This invention relates to screens for projecting systems in connectionwith moving pictures, stereopticon views, or the like, such screensbeing utilizable ordinarily for rear projection although, under somecircumstances, tliey may be utilized for iront projection.

The principal object of the invention is to provide a translucent screenon which the picture ma;` be projected in a lighted or darkened room atthe option of the operator. In screens of this type the picture isprojected from the rear; that is. projected on the screen on theopposite side from the spectator, the spectator being in the path of thedirect light instead of receiving the retlected light from the picture.

Another object is to provide a screen in which the light thrown by theprojectionl machine passes through the screen and gives the picture anappearance of unusual sharpf ness. -Another object is to provide atranslucent screen which is flexible and which may be readily rolled fortransportation or storage, the folds of the screen not. sticking to theadjacent fold when stored in a rolled condition.

Another objectis to provide a screen which may be adapted to varying;rclimatic condi-` tions, such as ditierenees in temperatures andluuuidity,by merely varying the quantity of the ingredients used,llcretofore screens of this type have been made but it has been foundthat a screen made of one. material adapted to be used under oneclimatic coudition will be wholly unsuitable if used under n ditiereutand widely vai-,vingr climat-ic condition, so that screens for warm,humid climates would have to be made of one material while screens forcold. dry climates would have to be made of other materials. ily thisinvention the dill'erenees in tenuwrature can be easily taken eare ot' br varying the relative quantities ol ingredients used without thenecessity of usine other and dill'erent. ingredients.

Another ohjeet of this invention is to provide a screen which will notmildew when left rolled in a damp place for along period of time.

Another object of this invention `is to provide a screen which will beV'ernilni" In other words. this inven ion relates to a screen which canbe made adaptable for all ranges of temperature and climate and whichmay be rolled indefinitely without deterioration and which will alsoproduce an image of unusual sharpness, and which can be used in alighted room as well as in a darkened one.

Other objects of the invention will appear from the foliowinggdescription. This screen is an improvement on the type of screendisclosed in Patent No. 1.151.502, issued to Troeger, on August- :2-l,1915.

, A very satisfactory screen has been produced by using the followingformula. The portions given are by weight- Parti Glue 100 'Water 208Sodium fluoride 4 Glycerine 100 Special formula 80 Cobaltblue 1.5

The `flue and `f vlycerine form the screen body and these materials mayhe any suitable character. The sodium fluoride acts as a gcrmieide, aluu'teriacide, fungicide, preservative or the. like and. in lieuthereof, other agents having similar properties may he utili'fzed. 'lluroba t lueserves as a lifhttilterine' agent it it. or equivalent materumay be utilized, if desired, to produce a screen otsuch character thatit will be neutral or nearly so when acted upon by the lightt' rom theprojector whereby a large number of the usual vellow rays of theprojecting light souri-e are tillered ont.

' In preparing the screen, the glue may be soaked for au extendedperiod. as from six tu eight. hours. and then brought into solution h va slow heat and frequent. stirring, the temlwrature. }uel'eralvl notgreatly exceeding ITS degrees l". lrel'erahly.the sodium lluoride isseparatel dissolved in water and added to the glue before the aforesaidhave been found to give extremely good reapplcaton of heat, sults intropics where only one part ot cupric Ibqglycerine may now bg added, thenuxsulphate is used. Obviously, 1n heu of cupricturejhereaftcr'being'tl'io'roughly stirred and sulphate, other agentshaving similar prop- 5 tireniijerrably'strained;" W'hilc the xnix'-crties may be utilized. o

Turc xs being stirred'a'nd while maintained 0n the accompanying drawing,we have substantially at the same temperature asillustratedascreen-formingarrangementand noted above, it is desirablethat the special on said drawing:

formula be added, the latter preferably hav- Figure 1 is a perspectiveview, partly in in" been previously strained. section, showing lthematrix or table upon lPreicrably, the cobalt blue coloring mawhlch thescreen is supported during` manuterial is stirred in last, this materialbeing facture thereof; added a few drops at a time until the proper Fig.2 is a transverse, vertical sectionrl coloris reached. After the mixturehas cooled View of the table of Fig. 1 and showing a some or 40 degreesF., its consistency frame above the table with a stretched sheet soshould be about that of a medium syrup at tl1er eon; room temperature.It'. on account of the type Fig. 3 is a vertical, sectional view of aporof glue used, the solution should be too thick, tion of the screenbefore the sheet is embedded more ot the sodium fluoride in watersolninthe viscous screen material; and 2 tion may be added. The moldingoperation Fig. 4 1s a view corresponding with Fig. 3 8J may now follow.showing the finished product.

d'I`l\ e special formula is usednas` a dilusgl As shown on the drawing,a drj7 sheet 1 or light-dill'using agent, and alsoservesas 0f .Suitablefabric, as georgette silk, from adatxnospherie agent* in the sense thatthe `whlclunfgrease'ad other'material have n 25 completed screen isthereby'put in a condibeen suitablyv removed. is stretched on a 'o tionresisting the otherwise damaging efframedetining an openingjust largeenough fects of the atmosphere. Preferably, the totsnugly around theupright edge or wall3 special formula is prepared as followszvto 4of thematrix table -l on which the screen parts of casein b vweight is added20S is to be molded. n 3 parts of water, 12.5 parts of borax, and 1 partAfter the matrix table has been brought of cupric su`q)h.xte.- Themethod of preparto suitable temperature conditions, ordinaring thisformula is as follows: ily above 100 degrees F., and with the screen-The casein is placed in parts of water forming -material in propercondition, and and stirred until all of the casein has been `of propertemperature, preferably somewhat moistened. The borax and cupricsulphate higher than the table temperature. said mateare dissolved withthe remaining 7S parts of rial should be poured on or applied to thewater and added to the casein mixture during table, preferably to suchan extent that it gentle stirring of the latter. The mixture slightlyoverflows the aforesaid wall 3, the

will then begin to thicken and within fortyheight of which determinesthe thickness of eight hours will have become a thin smooth the screen.The excess material should now 1` fluid which should be well stirred andleft be removed, as bya straight edge. :titer this to ripen for asuitable period. as tive days, operation, the molded material T is flushl. more or less, after which it is ready for use. with the top surfaceof the aforesaid wall 3 "f/ The casein serves as a 1ightdh'fnsingagentas shown particularly in Fig. '2. I n" After the excess material hasbeen removed 1o ntffhwa fer`ire'r`1'l'1n'enint may vary some;

what. dcpendi'ngupon the type thereof. Ohas stated above, the sheet ofsill: is suitably inSIy', in' accordance with certain phases of loweredtoward and into engagement with our invention, other light-diiusingagents the upper surface of the material on the mai maybe substitutedfor the casein. The horax trix table, care being taken to avoid cntrapnfunctions as a solvent for the casein. ment ot' air between the silksheet and the l `.Thc cupi-ic sulphate serves primarily as an,vscreen-forming material. In so doing. the agent resisting action of theatmosphere on frame holdingr the sill: sheet comes into posi- "thecompleted screen; it actsin an antih`vdro tion around the borderingTwall 3 ot the ma- "scopie manner and serves to' harden, dry trix table.and thereupon the silk sheet sinks o and/or cure the. screen. Therefore.the use into or auialgznuatcs with the screen-forming of cupric sulphaterenders the screen more material. At this time` application ol heatmoistnre-rcsisting without materially deto the matrix table `should hedscontinnml trat-ting from its elasticity and llexiblity. :nuhaftcr asuitable coolingr period. as two or 'hilcthcamountol'cnpricsulphatehasbccn three hours. has elapsed. a knife should he V.-3 given ns- 1 mrt.- where it. is known that the passed between the frame'.2 and the wall :l to scrccn is tolm used in a tropical climate. thissever said sheet. from its frame. 'l`lu\rcal'tcr. amount may heincreased from l to :l parts the molded screen may be removed from thein order to incl-case the moisture-resisting nuurixtahlc in :invsuitablc manner. properties of the screen. llowcrcr. screens l'lcrcompletion of thc screen as just dc- 1:.) made in accordance with theformula as given scribed, the edges thcreol should be suitably v bound,as by canvas strips, or equivalent, adhesively secured thereto andprovided with eyelets. When the screen is installed for use, a suitableframe should be provided and the screen positioned tautly therein, as bya rope passed through the eyelets and engaging the frame.

Although we have described the screenforming material of our inventionas formed into a' completed screen by a molding operation and utilizedin connection with a fabric sheet, it shall be understood that ourinvention is not to be so limited since the fabric sheet may be omitted,if desired, and the molding operation may he effected otherwise than asherein described.

'While the invention has been described with respect to a certainparticular preferred example which gives satisfactory results, it willbc understood by those skilled in the art after understanding theinvention, that various changes and modifications may be made withoutdeparting from the .spirit and scope of the invention and it is intendedtherefore in the appended claims to cover all such changes andmodifications.

'hat is claimed as new and desired tobe secured by Letters Patent is:

1. A projection screen containing gglatinous material. glycerine and aliquid principally, a light -diffusing agent, a curing agent, ngcrinicidgand having a fibrous strengthening material incorporatedtherein, said light diil'iising agent being substantially uniformlyincorporated in the other screen-forming materials.

2. A projection screen containing glue,

glyccrine and a liquid. principally, alight diffusing ugent, a germicidesubstantially incapable of exercising a hardening effect on the screen,a curingagent, eQl oi -ing material, and having a reinforcing materialin-v corporated therein.

3. A projectionl screen composed principally of gelatinons material,glycerine and water and containing a light diffusing agent, a curingagent, and having a tiberous strengthening material incorporatedtherein, said light dill'nsing agent being substantially uniformlyincorporated in the other screenforining materials.

4. A projection screen resistant to atmos-` pheric and climaticconditions comprising a fibrous hase incorporated in a compositioncomprising a gclatinons material and casein.

5. A lcxihlc. projection screen resistant to atmospheric. and climaticconditions coniprising a lilii'ons hase incorporated in a coniposition`comprising gclatinous material, casein and cupi-ic sulphate.

(l. projection screen resistant to atmospliric and climatic conditionscomprising a libi'ous hase incorporated in a composition comprisinglill) pai-ts ol' glue, Uh pai-ts of water, 10 parts of sodium fluoride,10U parts atiiious iiaterial,

'of glycerine and 80 parts of a composition comprising parts of casein,130 parts of Water 12% parts of borax and 1 part of cnpric sulphate.

7. A projection screen comprising a body fnsing agent and alight-filtering agent sub-y stantially uniformly incorporated therein.

10. 'A projection screen comprising a body section having alight-diffusing agent, a lightfiltering agent, and a gerniicidal agentsubstantially uniformly incorporated therein.

v11. A projection screen containing gelatinoiis material, glycerine anda liquid principally, a light diil'using agent, a curing agent, agermicide, coloring material, and having a fibrous strengtheningmaterial ncorporated-therein, said light diffusing agent -beingsubstantially uniformly incorporated in the other screen formingmaterials.

1:2. A projection sci-een composed of gelf'lycerine anda liquidrincipally, idal agen an alka i, a curing gen co oring nia erial, andhaving a sheet of fibrous material incorporated tligrein. i 13.. Aprojection screen composed of gelatinuous material, glycerine, and aliquid principally, casein, sodium fluoride, borax, cupric sulpliate.'c`ol0ring material, and having al sheet of fibrous materialincorporated there- 1n.

In testimony whereof. ive have affixed our signatures to thisspecification.

ARTHUR C. PAYNE. DAVID F. NEVLXN.

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